The present invention relates to a bone screw with a shaft defining a longitudinal axis and with a head which can be brought into engagement with a bone screw receiving means of a bone plate for the releasable connection of the bone screw to the bone plate, wherein a securing element is provided for securing a connection between the bone screw and the bone plate, wherein the bone screw can be brought from a position of engagement, in which the bone screw is held on the bone plate, into a release position, in which the bone screw can be released from the bone plate, wherein the securing element can be brought from a non-securing position, in which the bone screw can be brought into the release position, into a securing position for securing the connection between the bone screw and the bone plate, in which the bone screw takes up the position of engagement.
Bone screws of the type described at the outset are used in surgery to fix bone plates to bone parts of a human or animal body. The advantage of these screws is the fact that the position of engagement can be locked and so the bone plate cannot become disconnected from the bone screw or screws when stressed. Locking elements are known, for example, which are arranged on the bone plate and are pushed over the head of the bone screw already screwed in. This has the disadvantage that a securing element must be provided at every opening in the bone plate. If, however, not all the bone screw receiving means of the bone plate are required, the securing elements arranged at the bone screw receiving means which are not used are also, strictly speaking, superfluous. In addition, it must be ensured prior to the insertion of the bone plate that all the securing elements are in the non-securing position. If this is not the case, all the securing elements must be transferred from the securing position into the non-securing position during the operation which increases the operation time unnecessarily.